It is currently 23 Jun 2017, 18:56

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# A certain telephone company offers two plans, A and B. Under

Author Message
TAGS:

### Hide Tags

Intern
Joined: 27 Jan 2012
Posts: 10
GMAT 1: 710 Q45 V41
A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

30 Jan 2012, 02:19
2
This post was
BOOKMARKED
00:00

Difficulty:

55% (hard)

Question Stats:

66% (02:43) correct 34% (01:47) wrong based on 354 sessions

A certain telephone company offers two plans, A and B. Under plan A, the company charges a total of $0.60 for the first 7 minutes of each call and$0.06 per minute thereafter. Under plan B, the company charges $0.08 per minute of each call. What is the duration of a call, in minutes, for which the company charges the same amount under plan A and under plan B? A. 2 B. 9 C. 15 D. 21 E. 30 [Reveal] Spoiler: OA Last edited by Bunuel on 21 Mar 2012, 12:31, edited 4 times in total. Edited the question Math Expert Joined: 02 Sep 2009 Posts: 39622 Re: Word translation [#permalink] ### Show Tags 30 Jan 2012, 02:30 3 This post received KUDOS Expert's post A certain telephone company offers two plans, A and B. Under plan A, the company charges a total of$0.60 for the first 7 minutes of each call and $0.06 per minute thereafter. Under plan B, the company charges$0.08 per minute of each call. What is the duration of a call, in minutes, for which the company charges the same amount under plan A and under plan B?

A. 2
B. 9
C. 15
D. 21
E. 30

Let the duration, in minutes, for which the company charges the same under plan A and plan B be t minutes.

Then under plan A the cost would be $0.6+0.06(t-7) and under plan B the cost would be$0.08t. We want these amount to be equal: 0.6+0.06(t-7)=0.08t --> 60+6(t-7)=8t --> t=9.

Hope it's clear.
_________________
Intern
Joined: 27 Jan 2012
Posts: 10
GMAT 1: 710 Q45 V41
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

30 Jan 2012, 02:55
Thank you very much... I charged 0,6 for each of the first 7 minutes
Manager
Joined: 10 Jan 2010
Posts: 185
Location: Germany
Concentration: Strategy, General Management
Schools: IE '15 (M)
GPA: 3
WE: Consulting (Telecommunications)
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

30 Jan 2012, 03:28
First 7 Minutes cost 0,6 cent regardless how long you pick up the phone (for Plan A). For every minute after it costs 0.06 cent
For each minute you call with Plan B it costs 0,08$When is Plan A = Plan B A: 0,6 + 0,06*(t - 7) B: 0,08*t --> 0,6 + 0,06*(t - 7) = 0,08*t t = 9 Answer B Manager Status: MBA Aspirant Joined: 12 Jun 2010 Posts: 176 Location: India Concentration: Finance, International Business WE: Information Technology (Investment Banking) Re: A certain telephone company offers two plans, A and B. Under [#permalink] ### Show Tags 30 Jan 2012, 08:49 0.08*t = 0.06*(t - 7)+0.6 t=9 Senior Manager Joined: 31 Oct 2011 Posts: 484 Schools: Johnson '16 (M) GMAT 1: 690 Q45 V40 WE: Asset Management (Mutual Funds and Brokerage) Re: A certain telephone company offers two plans, A and B. Under [#permalink] ### Show Tags 30 Jan 2012, 09:19 I saw this one recently as well, and was also getting the wrong number. I managed to correct it within the allotted time, and got t=9, B. _________________ My Applicant Blog: http://hamm0.wordpress.com/ Senior Manager Joined: 18 Sep 2009 Posts: 355 Re: A certain telephone company offers two plans, A and B. Under [#permalink] ### Show Tags 30 Jan 2012, 16:18 why dont we write this equation like this: number of minutes be X 0.6(7)+0.06(x-7)=0.08(x). whats wrong with this equation. according to manhattann word translation guide Ex: pay$10 for the first 2 CDs then $7 per additional CD. N is number of CDs bought. 10*2+7(n-2)=T.C what is the difference Math Expert Joined: 02 Sep 2009 Posts: 39622 Re: A certain telephone company offers two plans, A and B. Under [#permalink] ### Show Tags 30 Jan 2012, 16:44 TomB wrote: why dont we write this equation like this: number of minutes be X 0.6(7)+0.06(x-7)=0.08(x). whats wrong with this equation. according to manhattann word translation guide Ex: pay$10 for the first 2 CDs then $7 per additional CD. N is number of CDs bought. 10*2+7(n-2)=T.C what is the difference The red part is wrong because the company charges a total of$0.60 for the first 7 minutes and not $0.60 per each minute of the first 7 minutes. In your example I guess it's meant that$10 are paid for each of the first 2 CD's.

Hope it's clear.
_________________
Senior Manager
Joined: 18 Sep 2009
Posts: 355
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

30 Jan 2012, 21:44
Thank you very much bunnel. I got it. I need to concentrate more on wording of the problem
Retired Moderator
Status: 2000 posts! I don't know whether I should feel great or sad about it! LOL
Joined: 04 Oct 2009
Posts: 1662
Location: Peru
Schools: Harvard, Stanford, Wharton, MIT & HKS (Government)
WE 1: Economic research
WE 2: Banking
WE 3: Government: Foreign Trade and SMEs
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

02 Feb 2012, 11:20
+1 B

The equation to solve this question is:

$$0.6 + 0.06(x-7) = 0.08x$$

To make it easy, we can express it in this way:

$$60 + 6(x-7) = 8x$$

$$x = 9$$

_________________

"Life’s battle doesn’t always go to stronger or faster men; but sooner or later the man who wins is the one who thinks he can."

My Integrated Reasoning Logbook / Diary: http://gmatclub.com/forum/my-ir-logbook-diary-133264.html

GMAT Club Premium Membership - big benefits and savings

Manager
Joined: 28 Jul 2011
Posts: 238
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

21 Mar 2012, 14:20
Duration be x

0.08x = 0.60 + 0.06(x-7)
0.08x = 0.60 + 0.06x - 0.42
0.02x = 0.18

x = 9

Ans: B
Intern
Joined: 19 Aug 2011
Posts: 29
Concentration: Finance, Entrepreneurship
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

26 Mar 2012, 01:08
I think backsolving here would be a faster method than actually jotting down the equations.
Math Expert
Joined: 02 Sep 2009
Posts: 39622
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

31 May 2013, 06:23
Bumping for review and further discussion*. Get a kudos point for an alternative solution!

*New project from GMAT Club!!! Check HERE
_________________
Manager
Joined: 27 Apr 2012
Posts: 62
Location: United States
GMAT Date: 06-11-2013
GPA: 3.5
WE: Marketing (Consumer Products)
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

02 Jun 2013, 13:26
1
KUDOS
Let the total duration of the call be x minutes.

Plan A = 0.60 + 0.06(x-7)

Plan B = 0.08x

Since both the amounts charged are equal, 0.60 + 0.06(x-7) = 0.08x

-0.02x = -0.18

Hence x = 9 minutes
Intern
Joined: 02 Jul 2014
Posts: 12
Concentration: Marketing, Strategy
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

07 Jul 2014, 20:00
1
KUDOS
In the first 7 mins:
Plan A cost 0.6
Plan B cost 0.08*7=0.56
0.6-0.56=0.04 <- Plan A cost 0.04 more

After 7 mins:
Plan A cost 0.06 per min
Plan B cost 0.08 per min
0.08-0.06=0.02 <- Plan B will cost 0.02 more per min

To balance the cost between Plan A and B:
0.04=0.02*2

SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1857
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

07 Jul 2014, 21:31
Solved by plugging-in the options

For 2 Minutes,
Plan A = 7;
Plan B = 0.16

For 9 Minutes,
Plan A = 0.6 + 2* 0.06 = 0.6 + 0.12 = 0.72
Plan B = 0.08 * 9 = 0.72

_________________

Kindly press "+1 Kudos" to appreciate

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 15931
Re: A certain telephone company offers two plans, A and B. Under [#permalink]

### Show Tags

01 Sep 2015, 05:07
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: A certain telephone company offers two plans, A and B. Under   [#permalink] 01 Sep 2015, 05:07
Similar topics Replies Last post
Similar
Topics:
For telephone calls between two particular cities, a telephone company 2 25 May 2017, 15:31
A certain electric-company plan offers customers reduced rates for ele 2 25 Nov 2015, 12:42
1 If all of the telephone extensions in a certain company must be even 6 11 Jul 2016, 17:57
Telephone Company X's monthly charge 1 29 Nov 2012, 10:03
15 A certain telephone number has seven digits. If the telephon 11 28 Apr 2016, 22:26
Display posts from previous: Sort by